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Evidence of armored dinosaur’s last meal found in fossilized stomach



June 2 (UPI) — For the first time, scientists have recovered the remains of the last thing an herbivorous dinosaur ate. Researchers found the well-preserved stomach trapped inside the 110 million-year-old bones of a nodosaur, a kind of armored dinosaur called an ankylosaur.

Scientists have long speculated about the diets of dinosaurs, but concrete evidence has been hard to come by.

“Fossil stomach contents are quite rare. They are even rarer for herbivores,” Caleb Brown, palaeontologist at the Royal Tyrrell Museum in Canada, told UPI in an email. “There have only been about nine reports of this for herbivorous dinosaurs, and only two or three of these are well-supported. Many of these other reports are just plants co-occurring with dinosaur skeletons.”

But thanks to the poor luck of a single dinosaur, Borealopelta markmitchelli, researchers can definitively say that some dinosaurs ate plants, and that this particular dinosaur preferred ferns.

Researchers estimate that shortly after this particular nodosaur died, it was swept out to sea. As the dinosaur’s thorny, armor-plated body sank into the seafloor sediment, the disturbed mud entombed it.

Though soft body tissue preservation in dinosaurs is still uncommon, scientists are getting better at finding the rarity — in part, because scientists know where to look, including strata that has previously revealed soft tissue fossils.

“The preservation of soft tissues in fossils is a result of many factors, including rapid burial in fine sediments and lack of disturbance by scavengers,” Brown said.

Finding the remnants of the last meals of carnivorous dinosaurs isn’t uncommon, as bones are less fragile than plant material.

“The right conditions to preserve bone will preserve the bones of both the predator and the prey, whereas you may need different conditions to preserve both animal tissue and plant tissue,” Brown said.

In the case of this sea-buried dinosaur, the conditions were right for the preservation of bone, stomach tissue and plant material.

Researches sliced the ancient contents of the dinosaur’s stomach into extremely thin sections and examined them under powerful microscopes. Specific structures on the spores and leaves found in the slides helped researchers identify a variety of ferns that flourished during the Early Cretaceous.

The analysis of the ancient stomach contents — detailed in a new study published Tuesday in the journal Royal Society Open Science — allowed scientists to gain new insights into the ecology of Borealopelta markmitchelli.

The remnants of the dinosaur’s last meal suggest the species was a picky eater. None of the most common plants were found in the it’s stomach.

“It was selective in what it ate, eating some kinds of ferns and not others, and mostly ignoring the tough leaves of cycads and conifers, similar to animals today like deer which only eat the soft leaves of broadleaf trees and herbs,” study co-author David Greenwood, biologist at Brandon University, told UPI in an email.

The stomach contents also contained stones, known as gizzard stones. Many herbivore past and present purposely consume bits of rock to aid digestion. Researchers also found bits of charcoal in the dinosaur’s stomach.

“Many animals today self-medicate by eating charcoal, but we don’t know why Borealopelta was eating charcoal,” Greenwood said. “The charcoal though tells us this animal had been eating in an area that had experienced wildfire in the last 6 to 18 months, and was feeding on the lush and nutritious fern growth that grew after the fire.”

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Citizen scientists help improve space weather forecasts



Sept. 18 (UPI) — Data collected by citizen scientists have helped space weather forecasters more accurately predict when Earth will get hit by solar storms, according to a study published Friday in the journal AGU Advances.

When researchers supplement computer models with citizen scientist-collected data on the size and shape of coronal mass ejections, or CMEs, forecasts were 20 more accurate.

The supplemental data, collected by volunteers through the Solar Stormwatch citizen science project, also reduced forecasting uncertainty by 15 percent.

“CMEs are sausage-shaped blobs made up of billions of tonnes of magnetized plasma that erupt from the sun’s atmosphere at a million miles an hour,” lead researcher Luke Barnard said in a news release.

“They are capable of damaging satellites, overloading power grids and exposing astronauts to harmful radiation,” said Barnard, space weather scientist at the University of Reading in Britain. “Predicting when they are on a collision course with Earth is therefore extremely important.”

Because the speed and trajectory of coronal mass ejections vary dramatically, scientists have struggled to accurately predict when and where solar storms will hit Earth.

“Solar storm forecasts are currently based on observations of CMEs as soon as they leave the Sun’s surface, meaning they come with a large degree of uncertainty,” Barnard said. “The volunteer data offered a second stage of observations at a point when the CME was more established, which gave a better idea of its shape and trajectory.”

Researchers say the study supports the deployment of wide-field CME imaging cameras on space weather monitoring missions.

Real-time analysis of the images provided by the spacecraft cameras could help forecasters pinpoint solar storm threats days in advance, they said.

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Ancient footprints in Saudi Arabia help researchers track human migrations out of Africa



Sept. 18 (UPI) — Paleontologists have discovered a diverse assemblage of 120,000-year-old human and animal footprints in an ancient lake deposit in Saudi Arabia’s Nefud Desert, offering new insights into the trajectories of human migrations out of Africa, according to a study published Friday in the journal Science Advances.

A mounting body of evidence, compiled and published over the last two decades, has upended early theories that humans migrated out of Africa in one or two giant waves.

“As more and more fossils are discovered, it seems that humans repeatedly dispersed out of Africa and did so much earlier than previously thought,” study co-author Mathew John Stewart told UPI in an email.

“Precisely when, how often and under what conditions remain open questions,” said Stewart, a researcher at the Max Planck Institute for Chemical Ecology in Germany.

For answers to these questions, researchers have mostly looked to Africa and Eurasia, ignoring the Arabian Peninsula. Though it neighbors both Africa and Asia, evidence of human occupation in the region is scant.

“The area today is a hyper-arid desert, characterized by very little rainfall and large, expansive sand dunes,” Stewart said. “The conditions are not very amenable to the preservation of material and sediments. Significant erosion of sediments and the subsequent destruction of material, such as fossil remains, is unfortunately common.”

Paleoclimate data suggests that Arabia wasn’t always as dry as it was today, and a scattering of fossil discoveries has confirmed that humans were able to make forays into the Arabian interior when shifts in climate turned the peninsula’s deserts into grassland.

The ancient footprints found in the Nefud Desert, fossilized in an ancient lake deposit known as ‘Alathar’ — Arabic for “the trace” — suggests humans made one of those forays roughly 120,000 years ago.

“The age of the footprints are consistent with Homo sapiens fossils in the Levant, and suggests that there were multiple routes that humans took upon expanding beyond Africa,” study co-author Richard Clark-Wilson told UPI in an email.

“There is earlier evidence for our species moving into the Mediterranean environment of the Levant and southern Greece, but this is the earliest evidence of our species moving into a semi-arid grassland as Arabia would have been,” said Clark-Wilson, a postgraduate research student at Royal Holloway in Britain.

In addition to human footprints, researchers uncovered footprints left by elephants, horses and hippos, suggesting Homo sapiens weren’t the only species drawn to the open grasslands and water resources of northern Arabia. Research suggests it’s possible humans were following animals when they first moved into the region.

“Whats exciting about the animal footprints is that it closely ties human and animal movements around lakes in northern Arabia,” Stewart said. “Unlike most other records, footprints provide very high-resolution information, on the order of hours or days. Also, the animal footprints provide information on what the environment and ecology was like when these people were moving through the landscape.”

While the discovery of ancient footprints in Arabia suggests human movements out of Africa extended eastward into northern Arabia, Stewart said plenty of questions remain unanswered.

“Precisely what happened to these people during the more arid periods? How long did they occupy the Arabian interior? Where did they go?”

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Study: Commercial fisheries regularly catch threatened, endangered fish species



Sept. 21 (UPI) — Despite Australia’s international reputation for high quality marine conservation programming, new research out of the University of Queensland suggests Australia’s seafood eaters are regularly consuming engendered species.

The findings, published Monday in the journal Nature Communications, suggest the consumption of endangered fish species isn’t just a problem Down Under — it is a global crisis.

When researchers surveyed commercial catch and seafood import data, they found 92 endangered and 11 critically endangered species of seafood are being caught elsewhere before being imported and sold at grocery stores, fish markets and restaurants in Australia, Europe and elsewhere.

That’s because it’s perfectly legal for commercial fishers to catch species threatened with extinction. Additionally, seafood is not required to be labeled according to its species.

“This means that the ‘fish’, ‘flake’ or ‘cod’ that Australians typically order at the fish and chip shop could be critically endangered,” lead researcher Leslie Roberson said in a news release.

“Australian seafood is not as sustainable as consumers would like to think, and it’s definitely not in line with many of the large international conservation agreements that Australia has signed to protect threatened species and ecosystems,” said Roberson, a doctoral candidate at the University of Queensland.

Home to the Great Barrier Reef and tremendous marine biodiversity, Australia has earned a reputation for progressive marine conservation programming.

But according to the latest study, unsustainable seafood importation and consumption patterns can undermine conservation efforts at home.

“Australia imports around 75 per cent of the seafood we consume and is internationally regarded as having effective conservation and fisheries management policies,” said study co-author Carissa Klein.

“When importing seafood from other places, we are displacing any social or environmental problems associated with fishing to that place, which is likely to have less capacity to sustainably manage its ocean,” Klein, senior research fellow at the University of Queensland.

According to Roberson, Klein and their colleagues, the estimates for the number of threatened species currently being caught by commercial fisheries are quite conservative.

The study authors suggest that part of the problem is that the international seafood trade is highly complex, making it difficult to track and regulate. One part of a fish may be processed in China, but the rest may go to Europe, they said.

“A typical situation might look something like — a fishing boat operating in Australian waters, owned by a Chinese company, with a crew of fishermen from the Philippines,” Roberson said. “We don’t know what we’re eating — it’s really hard to trace seafood back to its origin and species because the industry is such a mess.”

Researchers suggest trade and importation rules can be put in place to encourage Australians to eat more local seafood, which can be more easily regulated for sustainability. Australian-farmed abalone and wild-caught sardines are two seafood sources that could ease pressures on threatened fish species.

“Improving the sustainability of Australia’s seafood trade policies could significantly benefit the ocean worldwide, as well as the billions of people that depend on a healthy ocean for their health and livelihoods,” Klein said.

“It should be illegal to eat something that is threatened by extinction, especially species that are critically endangered — if we can better coordinate fisheries and conservation policies, we can prevent it from happening,” she said.

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